Defence sector

The threat of terrorism has pushed security at WTWs and WwTWs up the agenda. Michelle Todd of Expamet looks at the advantages of secure fencing

There may not be much to steal at WTWs and WwTWs but the need to make perimeter fences less penetrable has risen significantly up the priority list.

Trespassing has become a big problem for the rail industry, leading to a move away from traditional fencing to more sophisticated security barriers. A WwTW might not have as many immediate dangers, nor is there as much land to protect as the rail network, but there is still lots of work to be done to replace basic fences that are a joke to vandals.

One water company is currently looking at nearly 30km of new fencing for just one site. This time, it will not be chain link, which represents no real deterrent, or a powder-coated welded mesh system, on which the weld can corrode and break.

Palisade fencing, which is assembled on site by bolting or riveting vertical pales to adjustable angle iron horizontals, is a familiar site. However, it is expanded metal mesh fabric that is proving to be the main choice of the water industry.

Formed from sheet steel in one continuous component, requiring no intersections or welds, expanded metal provides a highly durable and vandal-resistant perimeter protection. Its tight mesh pattern prevents handholds or footholds from being gained, and is extremely difficult to cut without specialist equipment. Mesh panels are heavy duty and clamped to posts with very strong anti-vandal fixings.

However, there are already issues affecting the purchase of security fencing, especially on quality, which not everyone feels is being adhered to. Colin Bates, Managing Director of Expamet says: “All too often, buyers only see or want to see the headline figure, the price per metre, and base their decisions on that. I would argue, though, that if they are meant to stick to British standards and then happen to find something at an appreciably lower cost, particularly in such a competitive industry, then they need to ask why.”

Bates, who is also chairman of the European Fencing Industry Association, has a point. Procurement departments should be able to work out for themselves what sort of maintenance will be involved, and whether there are any hidden costs such as extra end posts or special fixings. But, currently, there is no authority to police what has been supplied. British Standards recommends a thickness of 3mm but, according to Bates, some choose to use the standard’s lower end flexibility; a grey area and this can make a world of difference to price and quality.

He added: “As well as the correct thickness, buyers should ensure that the fencing has been hot-dip galvanised, and that the appropriate bolts have been supplied with the correct coatings – otherwise they will face all sorts of maintenance and security issues, especially failure due to rust, making it very easy indeed for intruders.”

Bates claims that eliminating the dubious practice of supplying undersized gauge thicknesses of fences can be achieved by purchasing materials by their weight, not their thickness. “If, say, 500m of fencing, supposedly 3mm thick, was a complete lorry load, yet you miraculously get 600m from the same product, then unquestionably, you are getting a thinner material. You have to be, because the vehicle can only take a certain weight.”

Bates continues: “Rolling mills are far more accurate than they used to be, so there is no excuse for producing thinner materials than the British Standard requires. It is up to the buyers to be more responsible and for a proper policing authority to check.

“Not only is it the thickness, coating and fixing quality that can be questioned but buyers should also be aware of the correct foundations required to ensure a fence is fixed to British standards.”

Water companies are increasingly seeking to remove risk and acknowledge their duty of care for people, without which they can be subject to negative publicity. Using organisations such as the Home Office Scientific Development Branch, European Fencing Industry Association, and the Association of Chief Police Officers (which runs a Secure By Design programme) would give independent impartial advice on the systems that have been tested and approved – not only to meet the British standards but varying levels of target hardening.

When upgrading, buyers need to be aware of the pitfalls because the consequences of specifying inadequate security fences are simply too great a risk.

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